Aim. Coexistence of depression and dementia for many years has been widely studied for many years. According to the authors for clinical practice, both psychiatric and psychological, it is also important to effectively differentiate between these disease entities. The aim of this study is to compare the implementation of the Trail Making Test (TMT) in patients diagnosed with depressive disorders and those with organic depressive disorders. Methods. A sample of 150 persons aged 18-68 years participated in the study. Patients who took part in the investigation were divided into three groups: depressive disorders (DD, n=50), organic depressive disorders (ODD, n=50) and healthy controls (C, n=50). Cognitive functions were evaluated by the Trail Making Test. Results. Relevant statistical differences among examined group were observed: in TMT part A: DD/ODD: p=0.006; DD/C: p<0.001; TMT part B: DD/ODD: p<0.001; DD/C: p<0.001. In both cases, patients with ZD group scored higher than patients from the OZD group, but lower than those in the control group. Conclusions. I. Patients with organic depressive disorders achieved significantly lower results than patients with depressive disorders in TMT. 2. Subjects with depressive disorder compared to the healthy control group achieved significantly lower scores in TMT. 3. The authors determined the TMT performance indicators differentiating between groups: TMT part A: C=20-40 sec., DD>40 sec. 90 sec.; ODD>90 sec.; TMT part B: C<60 sec.; DD>60 sec. - 180 sec.; ODD>180 sec.